UNIVERSITY    OF   CALIFORNIA   PUBLICATIONS 

COLLEGE  OF  AGRICULTURE 

AGRICULTURAL  EXPERIMENT  STATION 
BERKELEY,  CALIFORNIA 


THE,  CREAM  SUPPLY 


By  HERBERT  A.  HOPPER 


BULLETIN  No.  209 

(Berkeley,  Cal.,  January,  1911) 


BERKELEY 

THE   UNIVERSITY   PRESS 
1911 


Benj.   Ide  Wheeler,   Ph.D.,   LL.D.,   President  of  the  University. 

EXPERIMENT   STATION   STAPE. 

E.  J.  Wickson,  M.A.,  Director  and  Horticulturist. 

E.   W.  Hilgard,   Ph.D.,  LL.D.,   Chemist    (Emeritus). 

W.  A.   Setchell,  Ph.D.,   Botanist. 

Elwood  Mead,  M.S.,   C.E.,   Irrigation  Engineer.      (Absent  on  leave.) 

Lerov  Anderson,  Ph.D.,  Dairy  Industry  and  Superintendent  University  Farm   Schools. 

M.  E.  Jaffa,  M.S.,  Nutrition  Expert,  in  charge  of  the  Poultry   Station. 

R.  H.  Loughridge,  Ph.D.,   Soil  Chemist  and  Physicist    (Emeritus). 

C.  W.  Woodworth,  M.S.,   Entomologist. 

Ralph  E.  Smith,  B.S.,  Plant  Pathologist  and  Superintendent  of  Southern  California  Patho- 
logical Laboratory  and  Experiment  Station. 

G.  W.  Shaw,  M.A.,  Ph.D.,  Experimental  Agronomist  and  Agricultural  Technologist,  in  charge 
of  Cereal   Stations. 

E.  W.  Major,  B.Agr.,  Animal  Industry,   Farm  Manager,  University  Farm,   Davis. 

F.  T.  Bioletti,  B.S.,  Viticulturist. 

George  E.  Colby,  M.S.,  Chemist   (Fruits,  Waters  and  Insecticides),  in  charge  of  Chem.  Lab. 

H.  J.  Quayle,  A.B.,   Assistant  Entomologist,   Plant  Disease  Laboratory,   Whittier. 

W.  T.  Clarke,  B.S.,   Assistant  Horticulturist  and   Superintendent  of  University  Extension  in 

Agriculture. 
H.  M.  Hall,  Ph.D.,  Assistant  Botanist. 

C.  M.  Haring,  D.V.M.,  Assistant  Veterinarian  and  Bacteriologist. 
John   S.   Burd,   B.S.,   Chemist,   in  charge  of  Fertilizer  Control. 
E.   B.  Babcock,   B.S.,  Assistant  Agricultural  Education. 
H.  A.  Hopper,  M.S. A.,  Dairy  Industry,   University  Farm,   Davis. 
W.  B.  Herms,  M.A.,  Assistant  Entomologist. 

J.  H.  Norton,  M.S.,  Assistant  Chemist,  in  charge  of  Citrus  Experiment  Station,  Riverside. 
W.  T.  Horne,  B.S.,  Assistant  Plant  Pathologist. 

J.   E.   Coit,  Ph.D.,   Assistant  Pomologist,   Plant  Disease  Laboratory,   Whittier. 
C.  B.  Lipman,  Ph.D.,  Assistant  in  Soil  Bacteriology. 
R.  E.  Mansell,  Assistant  in  Horticulture,  in  charge  of  Central  Station  grounds. 

A.  J.   Gaumnitz,  M.S.,  Assistant  in  Cereal  Investigations,   University  Farm,  Davis. 

E.  H.  Hagemann,  Assistant  in  Dairying,  Davis. 

B.  S.  Brown,  B.S.A.,  Assistant  in  Horticulture,  University  Farm,  Davis. 

F.  D.  Hawk,#  B.S.A.,  Assistant  in  Animal  Industry. 

J.  I.  Thompson;  B.S.,  Assistant  in  Animal  Industry,  Davis. 

R.  M.  Roberts,  B.S.A.,  Field  Assistant  in  Viticulture,  University  Farm,  Davis. 

J.   C.  Bridwell,  B.S.,  Assistant  Entomologist. 

C.  H.  McCharles,   B.S.,  Assistant  in  Agricultural  Chemical  Laboratory. 
J.  C.  Roper,  Patron  University  Forestry  Station,  Chico. 

Mrs.  D.  L.  Bunnell,   Secretary  to  the  Director. 
E.  C.  Miller,  Foreman  University  Forestry  Station,   Chico. 
N.  D.  Ingham,  B.S.,  Assistant  in  Sylviculture,   Santa  Monica. 
John  T.  Bearss,  Foreman  Kearney  Park  Station,  Fresno. 

E.  H.  Smith,  M.S.,  Assistant  Plant  Pathologist. 
T.  F.  Hunt,  B.S'.,  Assistant  Plant  Pathologist, 

C.  O.  Smith,  M.S.,  Assistant  Plant  Pathologist,   Plant  Disease  Laboratory,  Whittier. 
M.  E.   Stover,  B.S.,  Assistant  in  Agricultural  Chemical  Laboratory. 
P.   L.  MoCreary,  B.S.,   Laboratory  Assistant  in   Fertilizer  Control. 

F.  L.  Yeaw,  B.S.,  Assistant  Plant  Pathologist,  Vacaville. 
F.  E.  Johnson,  B.L.,  M.S.,  Assistant  in  Soil  Laboratory. 
CHARLES   Fuchs,  Curator   Entomological  Museum. 

P.   L.   HlBBARD,  B.S.,  Assistant  Fertilizer  Control  Laboratory. 

W.  H.  VOLCK,  Field  Assistant  in   Entomology,  Watsonville. 

E.    I,.   MORRIS,   B.S.,   Field  Assistant  in  Entomology,   San  Jose. 

J.   S.   HUNTER,   Field  Assistant  in   Entomology,   San  Mateo. 

L.   M.    Davis,    B.S.,   Assistant  in   Dairy  Husbandry,   University  Farm,   Davis. 

I.    Bonnet,  Assistant  in  Viticulture. 

S.  S.   ROGERS,    B.S.,   Assistant   Plant   Pathologist,  Plant  Disease  Laboratory,  Whittier. 

B.  A.  Madson,    U.S.A.,  Assistant  in  Cereal  Laboratory. 

Walter  E.  Packard,  M.S.,  Field  Assistant  [mperial  Valley  Investigation,  El  Centre 

E.  E.  Thomas.  B.S.,  Assistant  Chemist,  Plant   Disease  Laboratory,   Whittier. 


THE   CREAM   SUPPLY 

By  HERBERT  A.  HOPPER. 


The  present  phenomenal  growth  of  dairying  in  California  calls 
specific  attention  to  the  necessity  for  a  more  general  understanding 
among  cream  producers  of  certain  well  recognized  factors  and  con- 
ditions, the  improper  control  of  which  may  unnecessarily  increase 
butterfat  losses  on  the  farm  or  reduce  the  quality  of  the  butter  made 
from  farm  skimmed  cream.  Much  depends  upon  the  care  the  cream 
receives,  and  too  great  effort  cannot  be  exerted  through  encouraging 
both  higher  sanitary  and  higher  economic  standards  on  the  majority 
of  California  dairy  farms.  So  far,  unfortunately,  little  systematic 
effort  has  been  made  along  these  lines.  It  might  at  first  seem  that  the 
logical  way  to  reach  the  cream  producer  is  through  the  creamery.  As 
yet,  however,  most  creameries  have  not  made  sufficient  difference  in 
the  prices  paid  for  different  grades  of  cream  to  command  the  respect 
of  the  producer  for  any  suggestions  they  might  make  looking  to  an 
improved  quality.  Then,  too,  the  idea  of  doing  things  extensively 
has  very  generally  concealed  the  ultimate  significance  of  trifling 
daily  losses. 

In  spite  of  these  conditions,  the  improvement  of  the  general  cream 
supply,  and  the  checking  of  butterfat  losses  on  the  farm  rests  in  a 
large  measure  with  the  creamery,  and  its  cream  solicitors.  The 
redemption  of  quality  demands  a  united  effort.  Some  of  the  sanitary 
and  economic  features  of  the  cream  supply  are  discussed  in  the 
following  pages  with  the  purpose  of  pointing  the  way  to  higher 
quality  and  greater  profits. 

SOURCES    OF    BACTERIA    IN    MILK. 

While  milk  as  secreted  in  the  udder  is  probably  sterile,  it  has  been 
repeatedly  shown  impossible,  except  in  rare  instances,  to  obtain 
milk  from  the  cow 's  udder  that  is  not  more  or  less  contaminated  with 
bacteria.  They  find  their  way  readily  into  the  inner  parts  of  the 
udder  through  the  milk  duct  and,  flourishing  in  the  presence  of  favor- 
able temperature  and  food,  they  are  washed  out  by  the  process  of 


116  UNIVERSITY  OF  CALIFORNIA — EXPERIMENT  STATION. 


An  open  sanitary  milking  stable  suitable  for  certain  parts  of  California. 


__-  '   \. 

Bi'iirry  t  v  ^ 

l 

An  excellent  type  of  shed  to  give  the  herd  the  necessary  protection  from 
sun  in  summer  and  rain  in  winter.  Such  a  shed  should  be  found  on  every 
dairy  farm.     Exposure  to  storm  cuts  down  production. 


Bulletin  209.  THE  CREAM  SUPPLY.  117 

milking.    Any  disease  of  the  udder  may  also  add  to  the  numbers  of 
bacteria  in  the  milk. 

The  most  abundant  contamination  usually  comes  after  the  milk 
has  left  the  udder.  Dirt  or  dust  from  the  cow,  hands  of  milker, 
utensils,  or  the  dust  of  the  stable,  may  add  large  numbers  of  bacteria. 
Strainers,  coolers,  bottles,  and  other  apparatus,  if  unclean,  may  like- 
wise prove  detrimental.  In  ways  too  numerous  to  mention,  the 
process  of  contamination  may  go  on.  Not  all  bacteria  are  harmful. 
Some  are  helpful  when  they  can  be  controlled,  and  others  seem  to  be 
without  detrimental  properties. 

CAEE    OF    THE    COW. 

From  the  sanitary  viewpoint,  it  is  more  essential  to  groom  the 
cows  than  the  horses.  Repeated  trials  show  that  where  good  stable 
conditions  obtain  from  day  to  day,  it  requires  not  more  than  one 
minute  to  properly  brush  the  flanks  and  sponge  and  dry  the  udder 
of  a  cow  preparatory  to  milking.  The  body  of  the  cow,  and  especially 
the  flank  and  udder  parts,  must  be  clean  and  free  from  dust  to  insure 
good  milk.  Bacteria  are  transported  upon  dust  particles.  Don't 
groom  the  cows  or  distribute  dusty  foods  or  litter  just  before  milking 
time.  Always  allow  sufficient  time  for  the  dust  to  settle.  It  is  cus- 
tomary to  reject  the  first  few  streams  of  milk  in  first-class  dairies,  as 
such  milk  is  of  poor  quality  and  likely  to  be  highly  contaminated  with 
bacteria  which  have  found  entrance  from  the  outside.  It  is  little 
short  of  a  crime  to  proceed  to  milk  a  filthy  cow  without  first  rendering 
her  parts  clean  by  scrubbing. 

The  wise  dairyman  will  maintain  healthy  surroundings  for  his 
herd  at  all  times.  The  losses  consequent  upon  neglect  of  this  kind  are 
too  serious  to  be  lightly  considered.  Only  healthy  cows  will  make 
the  best  use  of  their  food,  and  the  fact  that  they  are  perhaps  unsound 
raises  a  grave  question  as  to  the  wholesomeness  of  their  milk.  The 
consumer  is  coming  to  have  little  interest  in  questionable  milk,  except 
to  avoid  it. 

THE    STABLE. 

The  dairy  stable  must  always  be  substantial  and  well  built,  but  in 
most  parts  of  California  it  will  serve  its  purpose  as  well  if  of  inex- 
pensive design.  Light,  ventilation,  and  ease  of  cleaning,  are  the  main 
considerations.  Fortunately,  these  can  be  accomplished  at  a  much 
less  expense  than  is  usually  believed.  Concrete  floors,  gutters  and 
mangers  are  recognized  as  essential  to  a  well  ordered  dairy  stable. 
They  not  only   assist  in  securing  sanitary   conditions,   but   make  it 


118  UNIVERSITY  OF  CALIFORNIA EXPERIMENT  STATION. 


A  clean,  well  drained  cow  yard — essential  to  a  properly  kept  dairy. 


■J    * 

wk        *  IS        1  11 

Hi'                    "^^m 

*"■ 

FT  .;:''*  :*;''jC' 

wg^^inm^ 

Barn  of  a  careless,  thriftless,  dairyman.     Fertility  is  wasted  and  the 
milk   contaminated. 


Bulletin  209.  THE  CREAM  SUPPLY.  119 

possible  to  properly  save  all  the  fertility  in  the  manure,  as  well  as 
contribute  to  the  health  and  comfort  of  the  cows. 

Where  cows  are  to  occupy  the  stable  for  any  prolonged  period, 
the  usual  rigid  stanchion  should  give  place  to  the  modern  swing 
stanchion,  either  of  wood  or  wood  and  angle  iron ;  both  of  which  are 
sanitary  and  convenient.  The  overhead  litter  carriers,  as  well  as  the 
patent  mangers  and  watering  devices,  are  convenient  and  paying  in- 
vestments but  are  not  absolutely  necessary  where  the  capital  is  limited. 
A  definite  system  of  ventilation  is  hardly  necessary  in  this  state,  but 
light  should  be  provided  at  the  rate  of  four  square  feet  of  glass,  or 
its  equivalent,  per  cow.  It  is  unreasonable  to  assume  that  a  large  herd 
will  not  contain  occasionally  an  ailing  cow  so  that  the  use  of  disin- 
fectants in  the  stable  at  frequent  intervals  is  desirable.  The  periodic 
use  of  whitewash  is  essential  as  a  disinfectant,  and  to  present  a 
cleanly  appearance  throughout  the  stable.  The  stable  routine  should 
be  so  planned  as  to  have  all  operations  that  tend  to  raise  a  dust  take 
place  after  milking. 

THE    COW    YAED. 

Under  usual  California  conditions,  the  cow  yard  is  a  serious  handi- 
cap to  good  dairy  products.  In  summer  it  is  so  dusty  that,  whether 
the  cows  are  milked  in  it,  or  the  stable,  the  milk  is  greatly  contam- 
inated thereby.  In  winter  it  becomes  so  muddy  through  constant 
rains  that  it  is  unfit  for  use  except  to  further  contaminate  the 
milk. 

The  stable  should  be  set  well  up  on  a  firm  foundation  so  that  the 
yard  slopes  away  gently  in  all  directions.  The  use  of  gravel  is  to  be 
recommended.  Some  have  employed  concrete  to  conserve  the  manure 
and  make  sure  that  the  cows  are  kept  free  from  mud  and  filth.  The 
manure  should  be  removed  from  the  stable  daily  and  all  parts  of  the 
yard  cleaned  every  few  days.  This  reduces  the  number  of  flies  and  the 
contamination  of  the  milk. 

The  practice  of  "milking  in  the  corral"  is  possibly  doing  more  to 
retard  sanitary  dairy  progress  in  California  than  any  other  custom. 
Where  the  milk  from  such  dairies  goes  to  cheese  factories,  it  produces 
a  gassy  curd  and  a  low  grade  cheese ;  when  used  for  market  purposes, 
it  either  fails  to  keep  or  may  be  the  cause  of  digestive  disorders  in  the 
consumer.  A  specific  legislative  act  preventing  such  practices  would 
do  much  to  improve  the  condition  of  the  milk. 


120 


UNIVERSITY  OF  CALIFORNIA EXPERIMENT  STATION. 


Test  tubes  containing  the  actual  amount  of  dirt  or  manure  that 
would  fall  into  the  open  pail  from  forty  cows  if  milked  while  their 
udders  were  in  the  condition  indicated. 


A  clean  cow  and  a  clean  milker — essential  to  pure  milk  or  high-grade 
butter.     The  big  problem  before  California  dairymen  to-day. 


Bulletin  209.  THE  cream  SUPPLY.  121 


THE    MILKER. 

In  some  ways  the  quality  of  the  milk  is  dependent  to  a  very  great 
extent  upon  the  milker.  His  personal  habits  are  everything  in  deter- 
mining the  cleanliness  of  the  product.  He  should  be  personally 
clean — have  cleanly  habits  and  enjoy  perfect  health.  At  no  form  of 
farm  work  does  health  count  for  so  much.  Unless  the  regular  clothing 
is  above  suspicion,  it  will  pay  to  furnish  each  milker  with  a  frequently 
laundered  outer  garment,  to  be  worn  only  at  milking  time.  Milking 
with  dry  clean  hands  is  essential.  A  properly  equipped  wash  room 
is  an  inexpensive  but  paying  accessory  to  the  stable,  as  the  milkers' 
hands  will  require  an  occasional  washing,  even  under  the  best  of  con- 
ditions. The  practice  of  wetting  the  hands  in  the  milk  is  the  most 
repulsive  and  should  disqualify  any  milker  where  the  owner  has  any 
regard  for  his  business.  Much  is  gained  by  milking  in  a  quiet  manner, 
both  as  to  cleanliness  and  the  amount  and  quality  secured. 


MILKING  MACHINES. 

The  process  of  machine  milking  is  as  yet  in  a  state  of  incomplete 
development,  but  enough  studies  have  been  made  to  throw  some  light 
upon  the  relation  between  machine  milking  and  the  keeping  properties 
of  the  milk.  There  is  such  a  lack  of  uniformity  of  conclusion  as  to 
their  economic  advantages  that  this  phase  will  be  passed  over.  Suf- 
ficient to  say  that  many  report  them  a  paying  investment  and  that 
their  more  general  use  in  the  future  will  be  almost  a  necessity,  if 
present  tendencies  prevail. 

Any  device  for  milking  cows  that  offers  further  means  of  contam- 
inating the  milk  has  little  chance  to  survive.  At  present,  there  is  an 
abundance  of  rubber  tubing  and  numerous  intricate  devices  that  are 
more  or  less  difficult  to  clean.  Nevertheless,  with  reasonable  care  these 
devices  need  not  be  the  cause  of  further  contamination,  as  it  has  been 
shown  that  they  may  be  kept  in  order.  In  the  hands  of  a  careful 
operator,  the  quality  of  milk  drawn  by  a  modern  machine  will  show 
less  bacteria  than  most  milk  drawn  in  the  ordinary  manner.  Careful 
trials  have  been  made  to  sustain  this  conclusion.  The  protection  of 
the  milk  from  exposure  in  the  stable,  which  the  machine  offers,  is  a 
great  item  if  the  interior  surface  of  the  apparatus  is  clean.  All  rules 
for  care,  operation,  and  washing  of  a  milking  machine  must  be  relig- 
iouslv  followed. 


122  UNIVERSITY  OF  CALIFORNIA EXPERIMENT  STATION. 


The  ' '  Trueman ' '  sanitary  milk  pail. 

The  compulsory  use  of  a  simple,  practical  sanitary  pail  like  this  by 

California   dairymen  would  accomplish   great   good. 


"Trueman"   pail   inverted   for   steaming. 


Bulletin  209.  THE  CREAM  SUPPLY.  123 

UTENSILS. 

The  use  of  sound  utensils  free  from  rust  and  in  a  cleanly  condition, 
is  essential  to  good  milk.  Battered  or  dented  pails,  cans,  etc.,  and 
seams  that  are  not  flushed  with  solder  cannot  be  readily  cleaned  by 
reasonable  care  in  washing.  Such  uneven  surfaces  invite  contamina- 
tion that  is  readily  imparted  to  the  milk,  though  the  latter  is  sub- 
jected to  it  only  momentarily.  Such  utensils  are  employed  at  a  loss. 
New  pails  and  cans  may  cause  an  immediate  improvement  in  the  pro- 
duct. Eusty  cans  are  not  only  unsanitary,  but  the  raw  iron  is  shown 
to  be  slightly  dissolved  so  that  in  such  milk  the  action  of  rennet  is 
hindered.  An  essential  requirement  in  any  utensil  for  handling 
milk  is  simplicity  to  which  should  be  added  durability. 

SANITARY    MILK    PAILS. 

Nothing  will  contribute  so  much  to  the  cause  of  better  milk  as  will 
the  sanitary  milk  pail.  The  critical  period  in  the  life  of  milk  is  during 
the  time  of  milking.  Few  who  have  not  made  careful  tests,  realize  to 
what  extent  the  wide-open  pail  invites  dirt  as  compared  with  one 
wholly  or  partly  covered.  There  should  be  greater  interest  in  covered 
pails  and  dairy  operators  should  have  them  used  for  the  good  it  will 
do  their  business.  Realizing  that  the  dust  particles  are  the  carriers  of 
the  infection,  the  advantages  of  excluding  dust  are  obvious. 

There  are  several  styles  of  pails  that  are  efficient  in  excluding 
the  dust  and  falling  dirt,  but  some  are  rather  too  complicated  for 
general  introduction.  We  call  attention  here  to  the  Trueman  pail 
(shown  in  cut)  which  answers  all  practical  sanitary  requirements  and 
the  use  of  which  will  not  be  resented  by  milkers.  There  are  no  detach- 
able parts  to  become  foul  and  the  opening  permits  of  easy  cleaning. 
This  can  be  made  from  an  ordinary  pail  by  addition  of  the  visor. 

The  effect  of  the  covered  pail  in  excluding  dirt,  or  what  is  equiva- 
lent, bacteria,  may  be  seen  in  the  following  table  showing  figures  from 
three  different  farms. 

Table  I.  Bacteria  Per  Cubic  Centimeter. 

Stable  Condtions. 


Fair 

Above  average 

Poor 

Open  pail 

42,400 

33,150 

3,439,200 

Covered  pail 

6,430 

1,740 

103,600 

;'The  use  of  the  covered  pail  is  of  great  advantage  in  any  stable 
in  excluding  dirt  and  bacteria  from  the  milk.  The  relative  advantage 
gained  by  the  use  of  the  cover  depends  upon  the  sanitary  conditions 


124  UNIVERSITY  OF  CALIFORNIA — EXPERIMENT  STATION. 

of  the  stable."  When  a  strainer  of  any  kind  is  used  and  it  holds  the 
dirt  to  be  driven  throngh  later,  it  is  of  no  advantage  and  may  increase 
the  germ  content.  The  merits  of  the  covered  pail  should  appeal  to 
California  milk  producers. 

WASH   BOOMS. 

Using  an  original  can  of  warm  water  to  rinse  a  dozen  dirty  ones 
should  in  no  wise  be  considered  as  in  any  way  meeting  the  require- 
ments of  washing.  An  appropriate  room  with  means  for  obtaining 
hot  and  cold  water  with  wash  sink,  draining  rack,  and  steam  jet  for 
sterilizing  are  the  least  that  can  be  expected  in  the  way  of  washing- 
equipment.  This  room  may  or  may  not  be  separate  from  the  separ- 
ator and  milk  handling  room.  It  will  be  better  if  separate,  and  if 
milk  is  bottled  and  handled  in  any  quantity  the  wash  room  should  by 
all  means  be  entirely  by  itself.  The  separator,  bottling  apparatus 
and  refrigeration  facilities  should  be  at  least  grouped  by  themselves 
in  one  room,  while  the  washing  should  be  associated  with  the  power 
plant,  if  there  is  one.  Nothing  short  of  a  good  cement  floor  meets  the 
needs  of  a  wash  room  or  a  dairy  house  in  view  of  its  lasting  properties, 
comparatively  low  expense  and  greater  sanitation.  The  side  walls  of 
the  milk  house  should  be  tight,  and  there  should  be  an  abundance 
of  light  provided  for.  Windows  and  doors  should  be  screened  summer 
and  winter,  and  milk  or  cream  vats  provided  with  cheesecloth  or 
wire  gauze  screens  to  protect  contents  from  such  flies  as  gain  entrance 
to  the  room.  Where  one  is  working  for  a  reputation  for  his  products, 
the  importance  of  these  precautions  is  paramount. 

WASHING. 

Washing  dairy  utensils  is  an  important  operation,  though  it  in- 
volves but  a  few  simple  considerations.  Always  use  a  brush;  never 
nse  a  cloth,  as  the  latter  cannot  be  kept  in  a  sanitary  condition.  First 
rinse  the  utensil  in  cold  or  hike  warm  water — never  hot  water — as 
the  latter  tends  to  cook  the  milk  fast  to  the  tin.  In  this  way,  the 
bulk  of  the  adhering  milk  is  removed.  Then  water  should  be  used 
containing  sal  soda  or  washing  powder,  but  under  no  circumstances 
should  soaps  be  used.  In  cleaning  cans,  the  standard  brush  is  very 
effective  as  it  gets  into  the  crevices  and  beneath  the  shoulder  of  the 
can  more  readily  than  anything  else.  Pails,  dippers,  etc.,  should  re- 
ceive the  same  treatment.  Thorough  rinsing,  after  scrubbing  in  hot 
water  and  washing  powder,  is  essential,  after  which  steaming  should 
take  place  over  a  steam  jet  or  in  an  oven  or  chamber  constructed  for 


Bulletin  209.  THE  CREAM  SUPPLY.  125 

the  purpose.  After  being  steamed,  the  different  pieces  should  never 
be  touched  with  a  cloth,  but  allowed  to  dry  of  their  own  heat.  This 
prevents  rust.  Exposure  to  sunlight  is  desirable  if  same  can  be  ac- 
complished away  from  the  dust.    By  all  means  avoid  the  dust. 

THE    MILK. 

Eecognizing  the  fact  that  the  time  of  milking  is  the  critical  period 
in  the  life  of  milk  or  cream  and  that  the  covered  pail  and  cleanly 
habits  of  milking  are  important  to  consider  as  influencing  the  keeping 
properties  of  milk,  it  is  always  desirable  to  remove  the  milk  from  the 
stable  to  the  milk  room  as  soon  as  practical  and  convenient.  This  con- 
tributes to  its  length  of  life.  Open  cans  or  pails  of  milk  should  never 
be  allowed  to  stand  unprotected  in  the  stable.  Either  a  few  pails  with 
covers,  or  a  larger  can  should  be  in  use  to  receive  the  milk  from  the 
milkers  and  be  transported  directly  to  the  milk  room  at  frequent  inter- 
vals. It  is  better  if  the  milk  is  poured  from  the  milk  pail,  not  in  too 
close  proximity  to  the  cows.  In  a  large  dairy  one  person  can  take  care 
of  the  milk  from  several  milkers  without  their  leaving  the  stable. 
In  some  dairies  the  milkers  pass  to  a  convenient  room  at  the  side  or 
end  of  the  stable  where  the  milk  is  placed  in  cans  for  prompt  removal, 
or  perhaps  it  is  strained  into  a  conductor  which  conveys  it  by  gravity 
to  the  receiving  tank  in  the  milk  room.  Circumstances  must  deter- 
mine the  best  method  to  follow.  Any-  system  that  succeeds  in  getting 
the  milk  promptly  from  the  cow  to  the  milk  room  without  contami- 
nation is  good,  providing  it  is  accomplished  with  a  minimum  amount 
of  labor. 

COOLING. 

All  milk  or  cream  should  be  subjected  to  prompt  cooling.  From 
an  elevated  receiving  tank  or  vat  it  can  be  led  directly  over  any  of 
the  approved  standard  milk  coolers.  These  are  of  different  design  and 
permit  of  the  milk  or  cream  passing  in  a  very  thin  layer  over  a  more 
or  less  extensive  surface,  the  inside  of  which  is  generally  cooled  by  the 
circulation  of  cold  water.  This  process,  if  rightly  carried  on,  may  ac- 
complish two  things — the  rapid  cooling  of  the  milk,  and  the  elimina- 
tion of  odors  therefrom.  The  aerating  effect  is  in  less  favor  in  recent 
years  than  formerly,  as  it  is  easily  seen  that  milk  which  is  properly 
drawn  from  clean  cows  should  have  no  * '  cowy ' '  odor,  and  that  if  good 
milk  happened  to  be  exposed  in  cooling  to  an  impure  atmosphere  it 
might  be  injured  rather  than  improved.  The  importance  of  cooling 
is  obvious,  but  the  air  of  the  room  where  it  is  done  must  be  pure. 
Clean  milk  may  be  put  directly  into  bottles,  sealed  and  cooled  without 


126  UNIVERSITY  OF  CALIFORNIA EXPERIMENT  STATION. 


A    suggestion    for    cooling    and    holding    separator    cream    that    can    be 
made  use  of  on  any  dairy  farm  in  the  absence  of  artificial  means  of  cooling. 


Methods  of  insulating  cans  for  delivering  cream  in  hot  weather.  Right 
hand — felt  cover;  middle — wet  burlap  cover.  Either  is  far  superior  to  the 
naked  can. 


Bulletin  209.  THE  CREAM  SUPPLY.  127 

any  ill  results  from  lack  of  aeration,  showing  that  with  proper  cooling, 
milk  that  is  good  at  the  outset  will  keep  in  perfect  condition  as  long 
as  necessary. 

Where  milk  or  cream  is  held  in  bulk  for  subsequent  delivery,  the 
cans  should  be  emersed  in  cold  water  with  a  temperature,  if  possible, 
as  low  as  50°  F.  In  many  parts  of  California  the  well  water  is  much 
warmer  than  this,  and  ice  is  out  of  the  question.  In  the  interior  parts 
of  the  state,  water  from  deep  wells  will  average  70°  F  during  the 
summer  months,  so  that  it  has  little  to  offer  in  the  way  of  holding  milk. 
In  fact,  under  these  circumstances,  milk  cannot  be  held  with  any  de- 
gree of  safety  longer  than  is  needed  for  its  prompt  delivery.  Under 
such  conditions  we  find  that  where  it  is  necessary  to  handle  and  hold 
milk  for  shipment,  artificial  means  of  refrigeration  are  resorted  to. 
In  many  parts  of  the  state  cold  water  is  available  in  abundance.  The 
water  for  stock  may  be  passed  through  a  convenient  tank  in  which 
the  cans  of  milk  are  emersed,  and  still  be  useful.  In  this  way  the  milk 
gets  the  benefit  of  the  original  cooling  and  the  water  serves  two  pur- 
poses. A  small  tank  for  this  purpose  is  shown  in  the  accompanying 
cut.  The  inflow  should  deliver  near  the  bottom,  and  the  outtake  at  a 
safe  distance  from  the  top  of  the  cans.  By  using  this  device  in  warm 
weather  with  water  at  70°,  it  was  possible  to  secure  the  following  re- 
sults. While  this  is  not  enough  cooling  for  milk,  it  would  help  very 
much  in  holding  heavy  farm  skimmed  cream  and  is  given  to  show 
what  might  be  done  where  cool  water  is  available. 


Table  II.                             Effic 

iency  of  Water 

Cooler. 

Eate 

of 

inflow,  75  gallons  per  hour. 

Periods 

h hour         1  hour 

1|  hours      2  hours 

2|  hoi 

Temperature,  air 

89             89 

89 

88 

88 

Temperature,  water 

70              70 

70 

70 

70 

Temperature,   Milk 

96             83 

77 

75 

74 

Milk,  untreated 

100         100 

98 

97 

95 

Milk  was  heated  to  100°  F. 

PROTECTION  IN  HAULING. 

The  hauling  of  milk  and  especially  cream  for  long  distances  is  a 
necessary  condition  imposed  upon  dairymen  in  most  parts  of  Cali- 
fornia. For  a  large  part  of  the  year,  temperature  conditions  are  un- 
favorable and  some  means  of  protection  from  the  hot  sun  is  absolutely 
necessary.  The  wagon  should  have  either  a  cover  of  its  own  or  the  cans 
should  be  protected  by  a  canvas  cover  over  all.  The  latter  practice  is 
the  more  common,  and  the  better  method  if  both  cannot  be  used,  as 


110° 

104° 

70 

73 

68 

70 

92 

96 

128  UNIVERSITY  OF  CALIFORNIA EXPERIMENT  STATION. 

it  is  more  helpful  in  keeping  out  the  dust  and  probably  offers  as  much 
protection  as  the  other  to  the  contents  of  the  cans.  In  spite  of  its  use, 
the  high  temperatures  often  seriously  affect  the  milk  or  cream,  and 
some  means  of  additional  protection  are  necessary.  Accordingly,  cer- 
tain forms  of  insulation  for  the  cans  have  been  devised  to  protect 
from  the  heat.  The  felt  can  covers  have  not  as  yet  been  used  to  the 
extent  that  they  evidently  should  be.  Wet  burlap  wrapped  about  a 
can  has  considerable  merit  as  a  means  of  keeping  the  contents  cool. 
To  test  the  efficiency  of  the  two  methods  under  identical  conditions 
the  following  figures  were  tabulated : 

Table  III.     Effect  of  Insulating  10  Gal.  Cans  in  Different  Ways. 

Milk  kept  in  the  Shade         Milk  kept  in  the  Sun 
Periods  Start    1  hr.     3  hrs.   5  hrs.    Start    ]  hr.    3  hrs.  5  hrs. 

Temperature  of  Air  9!)°       100°       99°        98°       114°      128° 

Temperature  of      f  Dry  felt  cover  60       62       65       66       60       65 

contents  of         \   Wet  burlap  cov.er       60       62       66       67       60       64 

can  (  No  cover  60       61       78       82       60       80 

The  figures  shown  indicate  the  marked  value  of  either  method  in 
keeping  milk  or  cream  in  good  condition.  Considerable  would  be 
gained  if  after  using  the  wet  burlap  or  the  dry  felt  cover,  the  hauling 
were  done  in  a  covered  wagon.  Keeping  in  the  shade  made  a  differ- 
ence of  from  3  to  7  degrees. 

THE    CREAM    SEPARATOR. 

All  that  has  been  said  thus  far  as  pertaining  to  the  improvement 
of  the  milk  supply  applies  with  just  as  much  force  to  the  production 
of  wholesome  cream.  While  the  cream  represents  only  a  small  portion 
of  the  original  milk,  it  has  a  comparatively  high  commercial  value 
and  any  unfavorable  influence  incident  to  the  production  of  the  milk 
is  likely  to  be  detected  in  the  cream. 

On  most  dairy  farms  the  cleanliness  of  the  separator  needs  first 
attention.  Like  any  other  piece  of  apparatus  for  handling  milk  or 
cream,  it  must  be  kept  scrupulously  clean.  The  disastrous  effects  of 
using  a  foul  separator  bowl  can  be  imagined  only  when  recalling  that 
all  cream  passing  through  it  becomes  seeded  with  the  bacteria  it  con- 
tains. Unless  the  cream  is  held  at  very  low  temperatures,  these  are 
sure  to  develop  bad  flavors  that  are  ultimately  carried  over  into  the 
butter  which  must  consequently  sell  for  less  than  otherwise.  This  one 
cause  of  bad  flavors  alone  levies  a  heavy  annual  toll  upon  California 
creamery  products,  that  could  as  well  be  saved.  The  bowl  must  be 
taken  apart  and  washed  each  time  it  is  used,  following  directions 
previously  given  for  washing  utensils.  This  is  imperative  nol  only  for 
sanitary  but  for  economic  reasons,  as  will  be  pointed  out  later. 


Bulletin  209.  THE  CREAM   SUPPLY.  129 


LOCATION  OF  SEPARATOR. 

When  a  separate  milk  house  is  available,  the  separator  should  be 
found  there  and  never  operated  in  the  stable  or  in  any  place  where 
the  air  is  impure  or  the  surroundings  bad.  We  have  seen  many  farm 
separators  placed  in  filthy  out-buildings  or  even  out-of-doors  where 
they  serve  as  lodging  places  for  the  poultry  of  the  farm  at  times  when 
the  machine  is  not  in  use.  Nothing  could  be  more  antagonistic  to 
quality.  In  fact  such  conditions  are  contrary  to  law,  placing  the  owner 
liable  to  prosecution.  A  simple  clean  room  with  solid  floor  and 
screened  windows  and  doors  can  be  made  to  answer  very  well  as  a 
place  to  separate  the  cream.  The  initial  cost  of  a  good  machine  is 
enough  to  emphasize  the  need  of  protecting  it  from  the  weather. 

OPEEATION  OF  THE  SEPARATOR. 

Each  machine  is  usually  accompanied  by  specific  directions  for 
setting  up  and  operating.  These  should  be  carefully  followed.  As- 
suming that  all  the  parts  are  properly  adjusted,  the  first  requirement 
is  a  firm  foundation.  WTith  care,  most  hand  sizes  can  be  set  upon  a 
solid  wooden  floor  so  as  to  run  satisfactorily.  Unless  it  is  a  firm  floor 
without  vibration,  it  will  not  do.  A  concrete  pier  with  bolts  imbedded 
for  attaching  2-inch  by  4-inch  or  4-inch  by  4-inch  pieces  to  which  the 
separator  may  be  lagged,  is  the  best.  All  vibration  is  thus  avoided. 
Pieces  of  2-inch  by  4-inch  bolted  to  a  cement  floor  may  be  made  to 
serve  as  well.  Care  must  always  be  observed  to  set  the  frame  per- 
fectly level,  as  otherwise  the  bowl  will  not  run  true.  Placing  a  machine 
upon  skids  to  be  moved  about  the  farm  is  a  questionable  practice,  to 
say  the  least. 

The  life  of  a  standard  separator  depends  upon  its  care  to  a  great 
extent.  One  that  is  allowed  to  become  gummy  or  dirty  may  wear  out 
in  a  year.  Keep  it  free  from  dirt  and  well  oiled.  Follow  directions 
as  to  number  of  turns  of  crank  per  minute,  as  a  uniform  pull  and  not 
a  series  of  jerks,  will  contribute  to  skimming  efficiency  and  the  life  of 
the  separator.  The  continued  use  of  a  light  grade  of  oil  such  as  is 
supplied  with  the  machine  should  be  followed,  as  .heavy  oil  gums  the 
parts.  An  occasional  run  on  coal  oil  is  said  to  clean  the  bearings  from 
gum  and  grit.  An  oil  cloth  or  canvas  cover  for  the  machine  when  not 
in  use,  is  quite  worth  the  while  in  keeping  dust  and  sand  out  of  the 
bearings. 


130  UNIVERSITY  OF  CALIFORNIA EXPERIMENT  STATION. 


VARIATIONS  IN  CREAM  TESTS. 

We  often  receive  requests  from  patrons  to  explain  the  variation 
in  cream  tests  from  one  delivery  to  the  next.  A  farmer  is  likely  to 
feel  that  when  the  milk  is  from  the  same  herd,  fed  and  milked  in  the 
same  manner  and  the  cream  separated  in  the  same  way,  that  the  per 
cent  of  fat  in  the  cream  should  not  vary.  The  fact  is,  a  uniform  test 
of  farm  separated  cream  is  more  indicative  of  dishonest  testing  than 
are  variations  of  a  few  points  between  different  deliveries.  The  aver- 
age cream  patron  is  likely  to  look  upon  a  sudden  variation  as  incorrect. 
It  is  true  that  great  care  is  needed  to  test  cream  accurately,  even  after 
the  samples  are  properly  taken,  but  variations  are  bound  to  occur  that 
are  entirely  due  to  conditions  under  which  the  milk  is  separated. 
These  conditions  are  such  as  affect  the  efficiency  of  skimming  or  the 
thickness  of  the  cream. 

CAUSES  OF  VARIATION  IN  CREAM  TESTS. 

These  may  be  listed  as  follows: 

1.  Smooth  running. 

2.  Speed. 

3.  Cleaning  of  the  separator. 

4.  Rate  of  inflow. 

5.  Temperature  of  milk. 

6.  Condition  of  milk. 

7.  Richness  of  cream. 

8.  Richness  of  milk  separated. 

9.  Amount  of  water  or  skim  milk  used  in  flushing  the  bowl. 

1.  Smooth  Running. 

No  machine  will  do  good  work  when  it  does  not  run  smoothly. 
Under  such  circumstances,  the  layers  of  the  milk  in  the  separator  bowl, 
instead  of  arranging  themselves  in  natural  order,  the  cream  in  the 
center  and  the  skim  milk  at  the  outside,  are  broken  up  and  mixed  by 
the  vibration  and  much  of  the  fat  is  likely  to  escape  with  the  skim 
milk.  If  the  bowl  runs  smoothly,  the  cream  and  skim  milk  are 
properly  separated  and  find  their  respective  outlets  without  inter- 
ference. In  a  series  of  trials  where  the  machine  was  not  level  and  the 
upper  bearing  loose,  the  average  per  cent,  of  butterfat  lost  in  skim 
milk  was 

Balanced,         .03  per  cent. 

Unbalanced,     .17 


Bulletin  209.  THE  cream  SUPPLY.  131 

2.  Speed. 

The  centrifugal  force  required  to  insure  the  efficient  working  of  a 
separator  of  any  kind  depends  upon  the  speed  of  the  bowl.  There  is 
a  certain  speed  at  whioh  every  machine  will  do  its  best  work.  To 
attain  this,  a  hand  separator  should  be  given  as  many  revolutions  of 
the  crank  per  minute  as  is  indicated  on  same.  Usually  a  lower  speed 
causes  loss  of  butter  fat  in  the  skim  milk,  but  a  higher  speed  is  without 
beneficial  effects,  and  may  prove  injurious  to  the  machine.  With  no 
change  in  the  adjustment  of  the  cream  screw  which  we  assume  in  this 
discussion,  excessive  speed  tends  to  increase  the  capacity  for  milk, 
giving  a  comparatively  rich  cream,  but  a  reduction  in  speed  will  give 
a  larger  proportionate  amount  of  cream  which  will  test  less.  While 
there  is  nothing  gained  by  excessive  speed,  the  greater  the  reduction 
of  the  number  of  turns  below  normal,  the  greater  is  the  loss  of 
butt  erf  at  in  the  skim  milk. 

Table  IV.        Average  Per  Cent,  of  Butterfat  Lost  in  Skim  Milk 

at  Different  Speeds. 

Turns  of  Crank  Test 

10  too  high,  .029  per  cent. 

Normal,  .029^ 

10  too  low,  .12 

20  too  low,  .21 

3.  Cleaning  of  Separator. 

It  is  a  noteworthy  fact  that  many  users  of  hand  separators  are 
negligent  in  its  care,  and  the  idea  seems  to  be  abroad  that  it  is  un- 
necessary to  wash  them  more  than  once  a  day  or  once  in  two  or  three 
days.  Nothing  could  be  farther  from  the  truth.  Even  when  the  bowl 
is  rinsed  with  warm  water,  there  remains  a  coating  of  slime  and  milk 
on  the  interior  parts  which  readily  undergoes  decomposition.  When 
next  used,  the  warm  cream  in  passing  becomes  contaminated  with 
bacteria  from  this  source  and  it  is  injured  beyond  repair.  Such 
cream  may  be  dangerous  to  health  and  it  is  certainly  unfit  for  butter- 
making.  The  repulsiveness  of  such  a  practice  should  be  enough  to 
condemn  it  it  to  all  intelligent  dairymen.  However,  there  is  also  an 
economic  loss  caused  by  an  unclean  separator  bowl  which  makes 
careful  washing  necessary  each  time  it  is  used.  With  an  unwashed 
separator,  butterfat  losses  in  skim  milk  are  increased.  The  following 
averages  of  a  series  of  trials  on  machines  in  otherwise  good  running 
condition  show  nearly  three  times  as  much  loss  from  unwashed  as 
from  washed  machines. 


132  UNIVERSITY  OF  CALIFORNIA — EXPERIMENT  STATION. 

Average  per  cent,  of  fat  in  skim  milk : 

Washed  each  time  used,      .038  per  cent. 
Washed  once  per  day,         .10 
From  this  it  is  obvious  that  regular  washing  as  described  for  all 
dairy  utensils  is  essential  to  best  results  with  the  centrifugal  cream 
separator. 

4.  Bate  of  Inflow. 

Each  machine  has  a  rated  capacity  and  any  tendency  to  force 
milk  through  in  greater  amounts  or  to  reduce  the  inflow  to  any  extent 
below  normal  may  have  serious  results.  It  is  important  that  each 
operator  note  the  rated  capacity  of  his  machine  and  regulate  the 
inflow  accordingly.  Forcing  milk  through  in  excess  of  capacity  tends 
toward  the  production  of  a  thinner  cream  than  that  of  normal  inflow, 
while  a  reduced  inflow,  other  things  being  equal,  gives  a  thicker  cream. 
Decreasing  inflow  below  a  certain  point  does  not  prevent  separation 
in  the  bowl,  but  the  skim  milk  and  cream  are  likely  to  escape  together 
through  the  skim  milk  outlet. 

Table  V.  Effect  of  Excessive  or  Reduced  Inflow. 

Average  i  Butterfat 
J  Cream  23% 


Large  inflow  >Skim  milk 

Normal   inflow 


145% 
f  Cream  29% 


Small  inflow 


|  Skim  milk  .028% 

f  Cream  30% 

)Skim  milk  .027% 


5.  Temperature  of  Milk. 

Warm  milk  separates  more  completely  than  cold  because  it  is  more 
fluid.  All  standard  separators  will  do  more  efficient  work  when 
the  temperature  of  the  milk  is  between  80°  and  90°  than  at  any  lower 
temperature,  and  any  claim  that  efficient  work  can  be  obtained  when 
lower  temperatures  are  employed  is  very  doubtful.  Variations  in  test 
due  to  temperature  are  perhaps  not  so  marked  as  those  due  to  speed. 
Not  more  than  three  to  four  per  cent,  variation  in  the  cream  is  due  to 
temperature  under  ordinary  conditions.  Using  cold  milk  gives  a  loss 
of  butterfat  in  the  skim  milk.  The  colder  the  milk,  the  less  the 
amount  of  cream  and  the  higher  the  test.  The  effect  of  using  different 
temperatures  upon  per  cent,  of  butterfat  lost  in  skim  milk  is  shown 
below. 


Temperature  of  Milk 

Average  Loss 

90°  F. 

.022  per  cent 

75°  F. 

.051 

60°  F. 

.12 

Bulletin  209.  THE   CREAM  SUPPLY.  133 

6.  Condition  of  the  Milk. 

Milk  as  it  comes  from  the  cow  is  in  best  condition  for  thorough 
separation.  It  is  then  in  a  high  state  of  fluidity  and  at  the  right 
temperature.  Sour  or  curdled  milk  separates  with  difficulty,  or  not 
at  all.  Milk  that  cannot  be  separated  while  "cow  warm"  should  be 
cooled  to  50°  F.  and  then  heated  to  85°  F.  previous  to  skimming. 
Slightly  sour  or  otherwise  suspicious  milk  must  be  well  stirred  before 
entering  the  bowl,  and  slight  underfeeding  should  be  practiced. 

7.  Richness  of  Cream. 

The  richness  of  cream  obtained  from  the  separator  is  regulated  by 
a  device  called  the  cream  screw.  While  many  other  factors  may  affect 
the  test  of  the  cream,  the  cream  screw  is  depended  upon  for  securing 
either  a  rich  or  thin  cream.  However,  it  is  not  changed  frequently 
and  is  therefore  not  the  common  cause  of  variations  in  test  which 
often  lead  to  friction  between  buyers  and  sellers. 

8.  Richness  of  Milk  Separated. 

"The  richness  of  the  milk  separated  affects  the  quality,  but  not 
the  quantity  of  cream  and  practically  the  same  amount  is  obtained 
whether  the  milk  has  a  high  or  low  per  cent,  of  fat."  "The  amount 
of  fat  lost  in  the  skim  milk  is  not  affected  to  any  appreciable  extent 
by  the  richness  of  the  milk  separated. ' ' 

9.  Flushing  the  Bowl. 

It  is  evident  that  any  variation  from  day  to  day  in  the  amount 
of  water  or  skim  milk  used  in  flushing  the  bowl  at  the  end  of  the  run 
will  have  a  marked  effect  upon  the  test  of  the  cream.  A  variation  of 
one  pint  in  the  amount  used  may  change  the  test  of  cream  from  two 
per  cent,  to  five  per  cent.,  depending  upon  the  amount  of  cream 
secured. 

Effect  of  Feed. 

The  richness  of  the  milk  of  a  cow  is  determined  by  inheritance, 
not  by  feeding.  It  has  been  proved  beyond  question  that  it  is  impos- 
sible to  feed  so  as  to  permanently  affect  the  richness  of  the  milk.  If 
milk  is  not  thus  affected,  the  cream  cannot  be. 

POSSIBLE    YEARLY    BUTTERFAT    LOSSES. 

The  following  table  compares  the  losses  incurred  on  a  herd  of 
forty  cows  for  one  year,  when  the  separator  is  operated  improperly. 
An  average  annual  yield  of  9,000  pounds  of  milk  is  assumed — 85  per 
cent,  skim  milk.    Value  of  butterfat,  33  cents. 


134 


UNIVERSITY  OF  CALIFORNIA — EXPERIMENT  STATION. 


VI. 

Test 

Amount 

Value 

How  Run 

Skim  Milk 

Butterfat  Lost 

Butterfat  Lost 

Balanced 

.03% 

91.8 

$30.29 

Unbalanced 

.17% 

520.2 

171.66 

10  turns  too  high 

.029% 

88.7 

29.28 

Normal 

.029% 

88.7 

29.28 

10  turns  too  low 

.12% 

367.2 

121.17 

20  turns  too  low 

.21% 

642.6 

212.05 

Washed  each  time 

.038% 

116.3 

38.37 

Washed  once  daily 

.10% 

306.0 

110.98 

Large  inflow 

.145% 

443.7 

146.42 

Normal  inflow 

.028% 

85.7 

28.27 

Small  inflow 

.027% 

82.6 

27.26 

Temp,  milk,  90° 

.022% 

67.3 

22.21 

Temp,  milk,  75° 

.051% 

156.0 

51.50 

Temp,  milk,  60° 

.12% 

367.2 

121.17 

AMOUNT  OF  BUTTERFAT 
LOST  IN   SKIMMILK 

FROM    FORTY   COWS   IN  ONE    DAY 


NORMAL 

SEPARATOR 

MILK  TOO 

SEPARATOR 

SEPARATOR 

SEPARATOR  • 

WASH  FIJI 

•  00L1>  WARN 

BOWL 

TURNED     , 

14BS 

BUT  ONCE 

SEPARATED 

UNBALANCED 

W  REVOLUTION'S 

*       DAILY 

60*  P. 

TOO  LOW 

VALUE  IN- 

VALUE  IN' 

•  VALPI  II 

VALUE  II  , 

VALUE  IN 

ONE  YEAR 

ONE  YEAR 

ONE  YKAR 

Op  YR4R 

ONE  YKAR  « 

S 24.48 

■     145.91 

$58.69 

$83.14 

.$102.71 

The  above  is  based  on  a  daily  yield  of  approximately  15  pounds  of 
milk,  with  butterfat  at  33%  cents.  The  data  in  Table  VI  is  for  cows 
giving  nearly  twice  as  much  milk. 


Bulletin  209. 


THE    CREAM    SUPPLY. 


135 


Under  good  conditions  there  will  be  an  unavoidable  loss  of  about 
75  cents  per  cow,  or  approximately  $30  on  the  herd.  Any  loss  greatly 
in  excess  of  this  amount  is  uncalled  for. 

MANAGEMENT    OF   THE    CREAM. 

Proper  facilities  for  handling  cream  to  best  advantage  are  not 
always  at  the  command  of  the  creamery  patron.  Where  cream  is 
intended  for  market  purposes,  it  should  be  cooled  and  promptly 
bottled.  Otherwise,  the  cream  should  be  placed  in  clean  cans  and 
immediately  cooled.  Emphasis  must  be  placed  upon  the  word  clean. 
Even  when  cans  are  properly  washed  at  the  creamery  and  not  allowed 
to  air,  when  opened  at  the  farm  they  may  give  off  a  foul  smell.  It  is 
safe  to  always  give  them  another  washing  and  time  to  thoroughly  air 
before  filling.  Attention  is  called  to  the  usefulness  of  the  water  cooler 
referred  to  in  Table  II,  and  the  accompanying  discussion  of  its  use. 
On  many  farms  where  cream  is  produced,  it  is  the  only  way  to  hold 
it  until  delivery,  and  a  serious  application  of  the  principle  there  out- 
lined will  materially  improve  the  grade  of  our  butter. 

With  cream  as  well  as  milk,  the  fresh  warm  portion  should  never 
be  added  to  that  already  cooled  until  it  has  been  reduced  to  the  same 
temperature.  Then  they  may  be  mixed  with  safety.  Otherwise,  the 
warm  cream  will  be  the  means  of  hastening  the  souring  of  that  already 


DONT  SKIM  TOO  1 

CREAM, 

VOLUME  OF  CREAM  IS  MISLEADING.  1 

ITS  T^"             T  THAT 

COUNTS* 

1 
IH               i 

1                   ffe*               - — "■"^         sP£ 

.,  isxozH 

|4  20/1 

The  jars  on  the  right  and  left  each  contain  cream  representing 
13 ^  oz.  butterfat,  as  shown  in  the  middle  jar.  Notice  difference  in 
volume.     Skim  a  reasonably  heavy  cream. 


136  UNIVERSITY  OF  CALIFORNIA EXPERIMENT  STATION. 

cooled.  The  milk-room,  where  milk  or  cream  is  held  and  cooled, 
should  be  used  for  no  other  purpose,  as  decaying  vegetables  or  other 
strong  smelling  products  will  surely  taint  the  cream. 

PROPER  CARE  AND  HANDLING  OF  CREAM  IS  EXACTING  WORK. 

While  it  is  true  that  careless  or  ignorant  employees  are  often 
trusted  with  the  milking  and  handling  of  the  product,  this  is  a 
dangerous  practice.  There  is  no  point  in  the  life  of  milk  or  cream 
where  a  reasonable  amount  of  mature  experience  and  judgment  will 
not  easily  pay  for  themselves.  Milk  is  so  readily  perishable  that  only 
trained  persons  should  be  trusted  in  its  care.  The  cost  of  producing 
it  makes  carelessness  a  dangerous  and  expensive  risk  to  take.  Probably 
no  form  of  human  food  is  produced  under  conditions  where  skill  and 
common  sense  count  for  more  than  in  the  production  and  handling  of 
milk  and  cream.  There  are  many  instances  where  children  and  other 
incompetent  persons  have  been  employed  to  cleanse  milk  bottles  and 
cans  and  fill  the  same  for  delivery.  It  is  hard  to  imagine  any  arrange- 
ment calculated  to  produce  disaster  more  vicious  than  one  of  this 
kind.  This  exactness  applies  not  only  to  milk  and  cream,  but  to  all 
forms  of  dairy  products. 

DELIVERY    OE    CREAM. 

It  is  said  that  99  per  cent,  of  the  cream  delivered  is  so  handled 
that  the  butter  made  therefrom  is  injured.  The  producer  should  have 
some  interest  in  the  delivery  of  his  product,  especially  if  he  has  given 
it  good  care  and  is  sending  it  to  a  cooperative  or  other  creamery  where 
quality  is  recognized.  It  is  desirable  that  the  time  from  the  cow  to 
the  churn  be  as  short  and  conditions  as  favorable  as  possible.  During 
a  large  part  of  the  year,  careful  covering,  and  the  insulation  of  cans 
as  referred  to  in  Table  III,  is  imperative  in  California.  It  is  remark- 
able how  much  may  be  accomplished  in  the  way  of  delivering  good 
cream  if  it  is  thoroughly  pre-cooled  and  well  insulated  in  transit. 
Why  this  is  universally  overlooked  is  beyond  comprehension.  It  is 
not  wise  where  the  herd  is  small  to  withhold  cream  four  or  five  days 
to  get  a  full  can.    Use  a  smaller  can  and  send  more  frequently. 

PRODUCERS'    AND    MANUFACTURERS'    RESPONSIBILITY. 

The  butter  interests  of  the  country  have  been  struggling  in  recent 
years  with  a  condition  of  declining  quality.  This  is  not  as  it  should 
be.  Greater  care  in  producing,  and  handling  the  cream  on  the  farm, 
and  in  its  transportation  and  manufacture  into  butter,  will  positively 


Bulletin  209. 


THE    CREAM    SUPPLY. 


137 


correct  it.  The  power  to  overcome  these  defects  lies  with  those  con- 
cerned with  the  different  steps  of  the  business.  It  is  not  that  more 
knowledge  is  needed,  but  that  a  better  application  of  facts  already 
understood  be  made.  The  California  cream  producer  or  creamery 
operator  who  overlooks  his  responsibility  in  this  regard  is  not  serving 
the  best  interests  of  the  industry. 

ACKNOWLEDGMENT. 

In  presenting  certain  data  in  this  bulletin,  Bulletin  116  of  the 
Purdue  University  Agricultural  Experiment  Station  has  been  drawn 
upon. 

Farmers'  Bulletin  201  is  recommended  to  those  who  care  to  study 
further  the  farm  separator  problem. 


1M  ,4^ 


A  satisfactory  cream  gathering  outfit.     Where  the  original  quality  of  the 
cream  will  warrant  it,  much  will  be  gained  by  insulating  each  can  as  well. 


STATION   PUBLICATIONS   AVAILABLE    FOR    DISTRIBUTION. 


REPORTS. 

1896.  Report  of  the  Viticultural  Work  during  the  seasons  1887-93,  with  data  regarding  the 

Vintages  of   1894-95. 

1897.  Resistant  Vines,  their  Selection,  Adaptation,   and  Grafting.     Appendix  to  Viticultural 

Report  for  1896. 

1902.  Report  of  the  Agricultural  Experiment  Station  for  1898-1901. 

1903.  Report  of  the  Agricultural  Experiment  Station  for   1901-03. 

1904.  Twenty-second  Report  of  the  Agricultural  Experiment   Station   for   1903-04. 


BULLETINS. 


Reprint.     Endurance    of    Drought    in    Soils 

of   the   Arid   Region. 
No.  128.      Nature,   Value   and   Utilization   of 

Alkali  Lands,   and  Tolerance  of 

Alkali.       (Revised   and   Reprint, 

1905.) 
133.      Tolerance    of    Alkali    by    Various 

Cultures. 
140.      Lands    of    the    Colorado    Delta    in 

Salton    Basin,    and    Supplement. 
142.      Grasshoppers    in    California. 
147.      Culture  Work  of  the  Sub-stations. 
149.      California   Sugar  Industry. 

151.  Arsenical    Insecticides. 

152.  Fumigation  Dosage. 

153.  Spraying  with  Distillates. 

154.  Sulfur   Sprays  for  Red   Spider. 
159.      Contribution      to     the      Study     of 

Fermentation. 

161.  Tuberculosis  in  Fowls.    (Reprint.) 

162.  Commercial    Fertilizers.      (Dec.    1, 

1904.) 
165.      Asparagus    and    Asparagus    Rust 
in  California. 

167.  Manufacture     of     Dry     Wines     in 

Hot  Countries. 

168.  Observations    on    Some   Vine    Dis- 

eases in   Sonoma  County. 

169.  Tolerance   of  the   Sugar   Beet   for 

Alkali. 

170.  Studies    in    Grasshopper    Control. 

171.  Commercial  Fertilizers.    (June  30, 

1905.) 

172.  Further  Experience  in  Asparagus 

Rust  Control. 
174.      A   New   Wine-cooling   Machine. 

176.  Sugar   Beets   in   the   San   Joaquin 

Valley. 

177.  A    New    Method    of    Making    Dry 

Red  Wine. 

178.  Mosquito  Control. 

179.  Commercial     Fertilizers.        (June, 

1906.) 

180.  Resistant  Vineyards. 

181.  The   Selection   of    Seed-Wheat. 


182.  Analysis     of      Paris     Green     and 

Lead  Arsenic.  Proposed  In- 
secticide  Law. 

183.  The    California   Tussock-moth. 

184.  Report    of    the    Plant    Pathologist 

to  July   1,    1906. 

185.  Report     of      Progress     in     Cereal 

Investigations. 

186.  The  Oidium  of  the  Vine. 

187.  Commercial     Fertilizers.        (Janu- 

ary,   1907.) 

188.  Lining  of  Ditches  and  Reservoirs 

to  Prevent  Seepage  and  Losses. 

189.  Commercial     Fertilizers.        (June, 

1907.) 

190.  The  Brown  Rot  of  the  Lemon. 

191.  California   Peach   Blight. 

192.  Insects    Injurious   to   the   Vine   in 

California. 

193.  The    Best   Wine    Grapes    for   Cali- 

fornia; Pruning  Young  Vines; 
Pruning   the    Sultanina. 

194.  Commercial      Fertilizers.        (Dec, 

1907.) 

195.  The  California  Grape  Root- worm. 

197.  Grape  Culture  in  California  :    Im- 

proved Methods  of  Wine- 
Making;  Yeast  from  California 
Grapes. 

198.  The  Grape  Leaf-Hopper. 

199.  Bovine  Tuberculosis. 

200.  Gum  Diseases  of  Citrus  Trees  in 

California. 

201.  Commercial      Fertilizers.        (June, 

1908.) 

202.  Commercial    Fertilizers.       (Decem- 

ber,   1908.) 

203.  Report    of    the    Plant    Pathologist 

to  July    1,    1909. 

204.  The  Dairy  Cow's  Record  and  the 

Stable. 

205.  Commercial    Fertilizers.      (Decem- 

ber,   1909.) 

206.  Commercial      Fertilizers.        (June, 

1910.) 

207.  The  Control  of  the  Argentine  Ant. 


CIRCULARS. 


No.      1.      Texas  Fever. 
3.      Hog  Cholera. 
5.      Contagious  Abortion  in  Cows. 
7.      Remedies  for  Insects. 
9.      Asparagus  Rust. 

10.  Reading  Course  in  Economic  En- 

tomology.    (Revision.) 

11.  Fumigation  Practice. 

12.  Silk  Culture. 

15.      Recent    Problems    in    Agriculture. 

What     a     University     Farm     is 

For. 
17.     Why       Agriculture       Should       be 

Taught    in    the    Public    Schools. 
19.      Disinfection   of   Stables. 

29.  Preliminary    Announcement    Con- 

cerning Instruction  in  Prac- 
tical Agriculture  upon  the 
University  Farm,  Davisville, 
Cal. 

30.  White  Fly   in   California. 

32.  White   Fly    Eradication. 

33.  Packing   Prunes   in   Cans.      Cane 

Sugar  vs.  Beet  Sugar. 
35.      Southern    California    Pathological 
Laboratory    and   Citrus    Experi- 
ment Station. 


36.  'Analyses  of  Fertilizers  for  Con- 
sumers. 

3  7.  Announcement  of  Farmers'  Short 
Courses  for   1908. 

39.  Instruction  in  Practical  Agricul- 
ture at  the  University  Farm. 

46.  Suggestions   for  Garden  Work   in 

California  Schools. 

47.  Agriculture  in  the  High   Schools. 

48.  Butter  Scoring  Contest,   1909. 

49.  Insecticides. 

50.  Fumigation  Scheduling. 

51.  University  Farm   School. 

52.  Information     for     Students     Con- 

cerning    the     College     of     Agri- 
culture. 

53.  Announcement  of  Farmers'   Short 

Courses  for  1910. 

54.  Some     Creamery     Problems     and 

Tests. 

55.  Farmers'    Institutes    and    Univer- 

sity   Extension    in    Agriculture. 
57.      Announcement  of  Farmers'   Short 
Courses  in  Animal  Industry  and 
Veterinary  Science. 


